Detoxification of arsenite by iodide in frozen solution.

The oxidation of arsenite (As(III)) to arsenate (As(V)) has received significant attention because it helps mitigate the hazardous and adverse effects of As(III) and subsequently improves the effectiveness of arsenic removal. This study developed an efficient freezing technology for the oxidative transformation of As(III) based on iodide (I-). For a sample containing a very low concentration of 20 µM As(III) and 200 µM I- frozen at -20 °C, approximately 19 µM As(V) was formed after reaction for 0.5 h at pH 3. This rapid conversion has never been achieved in previous studies. However, As(V) was not generated in water at 25 °C. The acceleration of the oxidation of As(III) by I- in ice may be attributed to the freeze-concentration effect. During freezing, all components (i.e., As(III), I-, and protons) are highly concentrated in the ice grain boundary regions, resulting in thermodynamically and kinetically favorable conditions for the redox reaction between As(III) and I-. The efficiency of the oxidation of As(III) using I- increased at high I- concentrations and low pH values. The low freezing temperature (below -20 °C) hindered the oxidative transformation of As(III) by I-. The efficiency of the oxidation of As(III) significantly increased using a fixed initial concentration of I- by subjecting the system to six freezing-melting cycles. The outcomes of this study suggest the possibility of the self-detoxification of As(III) in the natural environment, indicating the potential for developing an eco-friendly method for the treatment of As(III)-contaminated areas in regions with a cold climate. It also demonstrates radical remediation to almost completely remove a very small amount of As(III) that was input in As(III)-contaminated wastewater detoxification, a benchmark that existing methods have been unable to achieve.

Nutrition-Related Mobile Application for Daily Dietary Self-Monitoring.

Nutrition apps for mobile devices such as smartphones are becoming more widely available. They can help ease the arduous chore of documenting intake for nutritional assessment and self-monitoring. This allows people to control food intake, support their participation in physical activities, and promote a healthy lifestyle. However, there remains a lack of research regarding systematic analysis mapping studies in this area. The objective of this study is to identify dietary self-monitoring implementation strategies on a mobile application. This study analyzed 205 journals from the Scopus database using the descriptive-analytic method. The records used in this exploration study were those released between 2007 and 2021 that were collected based on the keywords "dietary self-monitoring," or "nutrition application," or "nutrition apps," and "calorie application." Data analysis was conducted using the VOSviewer and NVivo software analytical tools. The results show that research studies on dietary self-monitoring increased in 2017. Results also indicated that the country that contributed the most to this topic was China. The study on mobile applications for dietary self-monitoring revealed seven clusters of dominant themes: attitude to improved dietary behaviors, parameters for disease diagnosis, noncommunicable diseases, methods, nutrition algorithms, mobile health applications, and body mass index. This study also analyzed research trends by year. The current research trends are about dietary self-monitoring using a mobile application that can upgrade people's lifestyles, enable real-time meal recording and the convenience of automatically calculating the calorie content of foods consumed, and potentially improve the delivery of health behavior modification interventions to large groups of people. The researchers summarized the recent advances in dietary self-monitoring research to shed light on their research frontier, trends, and hot topics through bibliometric analysis and network visualization. These findings may provide valuable guidance for future research and perspectives in this rapidly developing field.

Chloroaluminate Ionic Liquid Immobilized on Magnetic Nanoparticles as a Heterogeneous Lewis Acidic Catalyst for the Friedel-Crafts Sulfonylation of Aromatic Compounds.

Chloroaluminate ionic liquid bound on magnetic nanoparticles (Fe3O4@O2Si[PrMIM]Cl·AlCl3) was prepared and used as a heterogenous Lewis acidic catalyst for the Friedel-Crafts sulfonylation of aromatic compounds with sulfonyl chlorides or p-toluenesulfonic anhydride. The catalyst's stability, efficiency, easy recovery, and high recyclability without considerable loss of catalytic capability after four recycles were evidence of its advantages. Furthermore, the stoichiometry, wide substrate scope, short reaction time, high yield of sulfones, and solvent-free reaction condition also made this procedure practical, ecofriendly, and economical.

Effectiveness of progesterone supplementation in women presenting low progesterone levels on the day of frozen embryo transfer: a randomised controlled trial.

INTRODUCTION: Progesterone is an essential hormone involved in the process of implantation and pregnancy maintenance. Evidence from recent studies has supported the importance of serum progesterone level around the time of embryo transfer in hormonal replacement therapy frozen embryo transfer cycles and recommended the need for individualised luteal support. Low progesterone around the time of embryo transfer is found to be associated with decreased rate of pregnancy after frozen embryo transfer. This single-centre, longitudinal, randomised, interventional controlled study aims to compare the rate of ongoing pregnancy between two groups of women with progesterone level below 10 ng/mL on the day of frozen embryo transfer: the study group using 800 mg vaginal micronised progesterone supplemented with 50 mg intramuscular progesterone per day and the control group using only 800 mg vaginal micronised progesterone. METHODS AND ANALYSIS: We enrol patients who are undergoing frozen embryo transfers with blastocyst-stage or cleavage-stage embryos and who satisfy the inclusion and exclusion criteria. After signing the informed consent, participants are randomised into two groups: the study group using vaginal micronised progesterone supplemented with progesterone intramuscular 50 mg per day and the control group using only vaginal micronised progesterone. Randomisation will be performed using R software at a 1:1 allocation ratio. Sequentially numbered, opaque sealed envelopes are used for allocation. The primary outcome is the rate of ongoing pregnancy. To demonstrate a difference of 10% with regard to rate of ongoing pregnancy, at least 370 participants per arm are required (type I error α=0.05, power=0.8). Assuming a dropout rate of 10%, a total of 824 patients (412 per group) will be invited. ETHICS AND DISSEMINATION: This study was approved by the Ethics Committee of Tu Du Hospital on 17 May 2021 (reference number: 1251/QD-BVTD). All participants provide informed consent before being enrolled in the study. The results of our study will be submitted to reproductive medicine conferences and journals. TRIAL REGISTRATION NUMBER: NCT04897269.

Fresh versus elective frozen embryo transfer: Cumulative live birth rates of 7,236 IVF cycles.

OBJECTIVE: To determine whether elective frozen embryo transfer (eFET), or the 'freeze-all' strategy, associated with better cumulative clinical outcomes compared with fresh embryo transfer (ET). METHODS: A total of 7,236 IVF cycles that were followed by a fresh ET or eFET between 2013 and 2017. The patients were subjected to controlled ovarian stimulation (COS) with a gonadotropin-releasing hormone (GnRH) antagonist protocol and cleavage-stage ET. Embryo cryopreservation was performed on day 3 by vitrification using an open system. A comparison of cumulative outcomes between the eFET (n=4,065cycles) and the fresh ET groups (n=3,171cycles) were performed. The analysis was performed in four groups of patients based on the number of retrieved oocytes: Group 1: poor responders (1-3 oocytes); Group 2: suboptimal responders (4-9 oocytes); Group 3: normal responders (10-15 oocytes); and Group 4: hyper-responders (>15 oocytes). The primary outcome was the cumulative live birth rate (CLBR) per stimulated cycle. RESULTS: There were a total of 10,283 ETs (n=5,639 eFET group; n=4,644 fresh group). The freeze-all strategy is associated with improved CLBRs in normal and hyper-responders, but not in suboptimal and poor responders. In Group 1, there were 351 IVF cycles and 387 ETs in total, and the CLBR was 14.3% and 17.7% (p=0.584) for the eFET and fresh group, respectively. In Group 2, there were 2,074 IVF cycles and 2,465 ET in total, and the CLBR was 25.1% and 23.3% (p=0.083) in the eFET and fresh group, respectively. There was a significant difference in the CLBR in Groups 3 and 4, favouring the eFET strategy. In Group 3, 2226 IVF cycles and 3243 ET were performed. The CLBR was 40.5% in the eFET and 36.6% in the fresh group (p<0.001). In Group 4, there were 2547 IVF cycles and 3,188 ET in total, and the CLBR was 52.2% and 47.7% (p<0.001) in the eFET and fresh group, respectively. The number needed to treat to achieve one additional live birth was 25.9 in Group 3 and 22.3 in Group 4. CONCLUSIONS: The implementation of the freeze-all strategy should be individualized. The freeze-all strategy is associated with improved CLBRs in normal and hyper-responders, but not in suboptimal and poor responders.

Reductive transformation of hexavalent chromium by ferrous ions in a frozen environment: Mechanism, kinetics, and environmental implications.

The transformation between hexavalent chromium (Cr6+) and trivalent chromium (Cr3+) has a significant impact on ecosystems, as Cr6+ has higher levels of toxicity than Cr3+. In this regard, a variety of Cr6+ reduction processes occurring in natural environments have been studied extensively. In this work, we investigate the reductive transformation of Cr6+ by ferrous ions (Fe2+) in ice at -20 °C, and compare the same process in water at 25 °C. The Fe2+-mediated reduction of Cr6+ occurred much faster in ice than it did in water. The accelerated reduction of Cr6+ in ice is primarily ascribed to the accumulation of Cr6+, Fe2+, and protons in the grain boundaries formed during freezing, which constitutes favorable conditions for redox reactions between Cr6+ and Fe2+. This freeze concentration phenomenon was verified using UV-visible spectroscopy with o-cresolsulfonephthalein (as a pH indicator) and confocal Raman spectroscopy. The reductive transformation of Cr6+ (20 µM) by Fe2+ in ice proceeded rapidly under various Fe2+ concentrations (20-140 µM), pH values (2.0-5.0), and freezing temperatures (-10 to -30 °C) with a constant molar ratio of oxidized Fe2+ to reduced Cr6+ (3:1). This result implies that the proposed mechanism (i.e., the redox reaction between Cr6+ and Fe2+ in ice) can significantly contribute to the natural conversion of Cr6+ in cold regions. The Fe2+-mediated Cr6+ reduction kinetics in frozen Cr6+-contaminated wastewater was similar to that in frozen Cr6+ solution. This indicates that the variety of substrates typically present in electroplating wastewater have a negligible effect on the redox reaction between Cr6+ and Fe2+ in ice; it also proposes that the Fe2+/freezing process can be used for the treatment of Cr6+-contaminated wastewater.